In the petroleum refining and chemical process industries, the oxidative polymerization of olefinic hydrocarbons during processing is a constant problem that leads to the fouling of process equipment which in turn leads to heat transfer loss, increased fuel and power losses, increased downtime for maintenance, and reduced product yield or purity. The oxidative polymerization of olefinic hydrocarbons thus results in the overall effect of reduced profits and increased safety risks.
Oxidative polymerization is a well known free radical process in which hydrocarbon hydroperoxides and hydrocarbon radicals are formed and the hydrocarbon radicals polymerize into gums or cross-linked polymers.
The present invention is a method by which the hydroperoxide content of a hydrocarbon stream can be determined to investigate or evaluate the fouling potential of a stream subjected to conditions that are conducive to fouling. This is important since the type and amount of antifoulant additive to be added to the process stream can be estimated based on its fouling potential. In addition, this method can be used in the laboratory or in the field to monitor process streams on a suitable periodic basis such as once a week to detect possible adverse changes in the process streams before they become a serious and expensive problem.
It is known from Banerjee et al., Analytical Chemistry (volume 36, no. 4, April 1964, pp. 792-796), that it is possible to make spectrophotometric determinations of peroxides in organic solvents by using acetic acid, chloroform and potassium iodide with the liberation of iodine. However, this method is rather complex and requires the use of a nitrogen purge as well as more toxic reagents.
It is also known from Baga et al., Analytica Chimica Acta (volume 204, 1988, pp. 349-353), that hydrogen peroxide can be spectrophotometrically determined in aqueous solutions using the color change of a copper/2,9-dimethyl-1,10-phenanthroline complex. This method is not applicable to the determination of organic peroxides since they are insoluble in the aqueous media.